1. Field of the Invention
The present invention relates to a packing material for liquid chromatography having a polyalkylene polyamine moiety linked through a spacer moiety as the pendant group to a porous silica gel coated with a silicone polymer and a process for production thereof.
2. Description Relative to the Prior Art
Liquid chromatography has been widely used for isolation and analysis of useful components from a natural product itself, production and working researches of various organic materials and isolation and analysis of a variety of compounds produced in those industries.
For example, a certain kind of liquid chromatography is suitable for the analysis of sugars, and for the analysis of these there have been employed, as the packing material, cation exchange resins comprising polystyrene gel possessing sulfonic acid groups (e.g., see Japanese Unexamined Patent Publication (Kokai) No. 59-162953), polystyrene resins possessing quaternary ammonium groups, silica gels having aminopropyl groups introduced therein (e.g., see Koizumi et al., Denpun Kagaku (Starch Science), 34, page 308 (87)) and ion exchangers having amino groups disclosed in Japanese Unexamined Patent Publication (Kokai) No. 60-150839.
All of the liquid chromatographies using these packing materials, although a separation ability to some extent may be expected, are not so satisfactory with respect to durability, elution conditions (e.g., the gradient method), etc. For example, the packing material such as silica type NH.sub.2 and polysaccharide having amino groups have some shortcoming, (1) poor in stability to hydrolysis, (2) the useable pH range is limited from 2 to 7, (3) the remaining adsorbed sample cannot be washed with an alkali, and the like.
The present invention is intended to provide a packing material for liquid chromatography which solves the problems of durability, handling and separation characteristics inherent in the prior art, and is particularly excellent in alkali resistance and separation characteristics.
The present inventors, particularly as a means for modifying the surface of inorganic solid particles excellent in physical strength to thereby impart stability of the organic residual groups derived to various chemical conditions, have proposed a method for coating the surface of those particles with a silicone polymer. Also, we successfully imparted a further function to the inorganic solid particles coated with the silicone polymer by utilizing the reactive groups of such coated silicone polymer, and reported publicly (see Japanese Unexamined Patent Publication (Kokai) No. 63-171678). These functional particles include many particles which can themselves be used as the packing material for liquid chromatography and can desolve aforesaid problems. However, as the result of further studies to develop a packing material having additional specific separation ability, present inventors are found that a packing material having a polyalkylene polyamine bonded, through a spacer with a certain chain length, to particles coated with a specific silicone polymer exhibits excellent separation characteristics particularly to sugars, etc., while retaining good stability, and then accomplished the present invention.